In recent years, there has been a growing concern about environmental problems in a variety of fields.
In the field of electrical power supply, among others, power supply by means of, for example, PV (Photo Voltanic) power generation and by the utilization of a secondary battery used in an electric vehicle (EV: Electric Vehicle) or a hybrid electric vehicle (HEV: Hybrid EV) has become a focus of attention. As such a secondary battery, a lithium-ion secondary battery is considered promising. The second battery is expected to replace of lead storage batteries and the like as the battery grows popular in future.
On the other hand, the service life of a lithium secondary battery is dependent on the ambient temperature thereof at the time of charging.
Hence, a study is being made of a technique extending battery life by controlling the ambient temperature of a battery by using a peltiert element (see, for example, Patent Literature 1).